86 951 Driver

Can this be done off the car? I have a spare mount I want to fill before putting it on. I have window weld already so that is what I will be using.

samluke

In my opinion, its best to do it when mounted on the crossmember, but if you make up a suitable mould it can be done dismounted. Its just as easy to take the member off fill and then re-install. I have a spare crossmember, you could borrow mine, make up a mount and give me back yours once its installed, it looks like we are close to each other.

86 951 Driver

I understand that filling the mount with it in the crossmember would be best, but I don't know if I like the idea of not being able to change the mount ever again. That is my concern. I live in North Kansas City, MO

BTW I am going to be using window weld on this project.

gt37vgt

perhaps consider rigging the mount up under abit of tension on some jig that way you get the extra volume of filler in that one might get if doing it in situ..but i don't think it would be a big deal..

mikey_audiogeek

Yep, that's what I did.

Cheers,
Mike

CurtP

If you're going to use window weld, then it isn't an issue. Take the mount off and fill the voids. Let it skin for 20 minutes, then reinstall. Let it cure for at least 24 hours before mounting the transaxle to it. But I don't care for the window weld method as you really don't know the durometer of the material and it doesn't fill the voids as well as the pour-in urethane.

If you use the pour-in urethane, you can still make the mount removable. I ground off as much rubber from mine before remolding, including all the rubber from the bottom. I used washers to space the mount off the crossmember which were removed after the urethane cured. I wanted the urethane to compress when the mount was installed.

Making the cross-member into the mould:


Release agent:


Final product:

86 951 Driver

I like window weld because 1. I already have it and 2. I want to just reinforce the stock mount. I used window weld on my 924S mounts and they were not completely solid, but the reduction in Wheel Hop was amazing. I'm not looking for reducing wheel hop here, just to stiffen it up more than what it is stock.

Your mount looks amazing CurtP I will say that.

User 41221

Out of curiosity, is there a specific problem you are trying to solve by using a filled tranny mount as opposed to just buying a new one? Seems the latter would be the easier way to go if you are suspecting this as the source of your noise.

+1 on Curts mount.

Scott H

Brilliant, hot glue! I used duct tape and cardboard when I did it... not so brilliant but it worked. No issues with NVH either. Would totally do this again instead of ever buying a mount unless I went to a fully solid metal mount, which I won't because my car isn't a track car.

86 951 Driver

I'm pretty sure my mount is trashed. I remembered that when I first got the car that I jacked the rear end of the car up by the transmission. I think that killed it.

My car makes that weird noise. Karl thought it was the rear wheel bearings and replaced those, but no change in the sound. So I'm thinking my transmission is rattling and the mount is toast so its just hanging there. Hopefully I'm right and the mount will fix it. I got a good used mount, I'm not going to fill it like the one above because I like to be able to undo mods. Just in case you never know. My old 924S had the early style mounts and the way I filled those it firmed up the trans alot had less wheel hop with no increase of noise. I'm not looking to reduce wheel hop I'm looking to fix my noise issue when being under a load.

Anyone in the KC area that is famaliar with these cars I will let you listen to the sound. Car drives great otherwise. Mechnically and highway city all that it does great, but once you go WOT it makes this bad noise coming from the back. It feels like something it being hit back there like a clunking/grinding noise. More a fast clunk though. But in normal street driving it does fine no noise almost at all.

Silver Rose

Usually a bad trans mount will make noise when loading and unloading. Like getting hard on throttle and then fully lifting. It is very rare that these mounts actually go bad, but is usually upgraded and filled in by racers or DE'ers like me.
I fear the noise you describe could be coming from the trans internals like the diff carrior bearings, could also be the axels. Before you go off the deep end I would trust Karls knowlage and let him take a listen!!

User 41221

Karl and I talked about this last night, and I know Karl has been very involved in trying to figure this problem out. Its not often that it takes Karl more than a day or so to identify a problem on a 951, so this one is a bit of a head scratcher.

If the mount doesn't take care of the problem, Jeff, you might want to get in touch with Cory (carbonrevo on rennlist), as he has a 951 tranny available for $500, if you wind up suspecting the tranny itself.

86 951 Driver

The trans was replaced before I had the car. I might call the PO to see if maybe he has any receipts or if Oklahoma Foreign knows about it.
I replaced the axles a few weeks ago.

I am going to see if the mount works. Hopefully I will be able to swap it in this weekend. I am going crazy trying to find this noise.

Karl thinks it might be suspension related or maybe maybe the trans mount. So I will swap out the trans mount since I already have one of those.

86 951 Driver

Wouldn't that show shavings or anything bad in the fluid?

User 41221

Not necessarily, if the tranny was flushed after the damage was done.